1. Field of the Invention
The invention relates to a extended television signal comprising signalling bits for conveying control information to control an extended decoder.
2. Description of the Related Art
Such an extended television signal has been described in the German patent application DE-A-41.12.712. This prior art document discloses a signalling bits signal comprising run-in information data, start information data, and useful information data. The run-in information data comprises eight sine oscillations for synchronizing a phase-locked loop. The start information data serves for addressing the useful information data and for catching the start of the useful information data. As soon as the receiver determines the presence of recognition data in the input signal, the receiver is able to process the useful information data with the correct phase. No further details with regard to the start information data are given. The useful information data are, for example, bi-phase coded. The signal is DC-free to facilitate magnetic recording.